html2canvas offscreen elements

 function hiddenClone(element) {
      var clone = element.cloneNode(true);
      var style = clone.style;
      style.position = 'relative';
      style.top = window.innerHeight + 'px';
      style.left = 0;
      document.body.appendChild(clone);
      return clone;
    }


  var el = document.getElementById('printEl');
  var clone = hiddenClone(el);

  html2canvas(clone, {
    onrendered: function (canvas) {
      document.body.removeChild(clone);
      var src = canvas.toDataURL();
      var img = document.createElement("img");
      img.src = src;
    }